Polypropylene (PP) is a semi-crystalline thermoplastic. High impact resistance, strong mechanical properties, resistance to various organic solvents and acid and alkali corrosion. Widely used in industrial fields, including packaging materials and labels, textiles (such as ropes, thermal underwear and carpets), stationery, plastic parts and various reusable containers, thermoplastic polymer equipment used in laboratories, speakers, automobile parts, polymer banknotes and so on. It is one of the common polymer materials. In 20 13 years, the global polypropylene market is about 55 million tons. Plastic coins in Britain, Australia and Canada are also made of polypropylene.

It is reported that the current global demand for PP materials is about 45 million tons per year, and it is estimated that the demand will increase to about 62 million tons by the end of 2020. The main application of polypropylene is the packaging industry, accounting for about 30% of the total consumption. Followed by electrical and equipment manufacturing, the consumption is about 26%. Consumption of household appliances and automobile industry 10%. Consumption in the construction industry accounts for 5%.

The surface of PP is smooth, which can replace some other plastic products, such as gears made of POM and furniture cushions. The smooth surface also makes it difficult for PP to bond with other surfaces, that is, PP cannot be firmly bonded with industrial glue, and sometimes it must be bonded by welding. Compared with other plastics, PP also has low density, which can reduce the weight for users. PP has excellent resistance to organic solvents such as grease at room temperature. But PP is easy to oxidize at high temperature.

Second, the use

Good dielectric properties, high-frequency insulation, not affected by humidity, but brittle at low temperature, not wear-resistant, easy to age. Suitable for manufacturing general mechanical parts, corrosion-resistant parts and insulating parts. Common organic solvents such as acid and alkali have little effect on it and can be used for tableware.

First, advantages

1, with a relatively low density of only 0.89-0.9 1, is one of the lightest varieties of plastics.

2, good mechanical properties, except impact resistance, other mechanical properties are better than polyethylene, and the molding processability is good.

3. High heat resistance, and the continuous use temperature can reach 1 10- 120℃.

4, good chemical properties, almost no water absorption, no reaction with most chemicals.

Second, the shortcomings:

1, the product has poor cold resistance and low impact strength at low temperature.

2. The product is easy to age due to light, heat and oxygen in use.

3, poor coloring.

4, easy to burn.

5. Poor toughness, high static electricity, poor dyeability, printability and adhesion.